Pulsator for fuel pumps



March 10, 1931. B', SMH-H PULSATQR FOR FUEL PUMPS Filed June 28,' 1928 Patented Mar. l0, 1931 UNITED STATEs rAfrENT OFFICE LUCIAN B.` SMITH, OF FLINT, MICHIGAN', ASSIGNB T0 A. C, SPARK PLUG COMBAN'Y,

-' 0F FLINT, MIQHIGAN, A COMPANY OF MICHIGAN' rutseron ron. rtm1. runs VApplication. led June 2 8, 1928. Serial 1.10. 289,049. This invention relates to systems for the mitted, this body being provided with an delivery of liquid fuels, as required by in- .'wardly concave part serving to lsupport ternal combustion engines used upon motor mentioned non-resilient diaphragm and said vehicles,or the like, `and the pulsator referred diaphragm being optionally protected by a 5 to is suitable to be used'upon, or in replaceperforated and downwardly concave guard A provide means, preferably suitable for use in chamber 12 and passage 16.

A the momentum that may be intermittently effective under compression, may be employed ment of, the outlet valve plug of a variable element which serves also to secure the edges stroke fuel pump,-s`uch as-for example, the of said 'diaphragm to said support, may be fuel pump disclosed in an application by best appreciated by the following description Abraham M. Babi'tch, Serial No. 123,370, 'of a specific embodiment thereof, taken in filed July 19,1926. connection with the appended claims and It is an object of this invention to provide` the accompanying drawing.

a novel flow-equalizingv unit, especially suit- The figure is, for the most part, a vertical able for use ima fuel delivery line, but in median section through avariable-stroke rewhose operation little or'no reliance is 'placed ciprocating fuel pump equipped with a pulupon the use of resilient metallic parts. satorembodying my invention.

A Various uses of a lenticular pulsator unit Referring externall and generally resembling that Shown in the mentioned drawing, a main upon which protection is herein sought have pump casting 10 is shown as associated with been described and claimed in an application` a closure plate or casting 11; and one of these bv Joseph Zubaty and Abraham M. Babitch,` "castings may. comprise a pump chamber 12 rstto the conventional features S.. N. 288,7 55, filed June 27, 1928"(13-102 114 ;vwhose volume is variable by reciprocation of but the present invention differs in princip e a pumping element such as a diaphragm 13. therefrom in that use is herein made of a so- A diagonally extendinginlet passage 14 may called slack-cloth or' similar. diaphragm, be controlled by means such as an inwardrather than a metallic or other resilient dialy openingevalve at 15; and an outlet or fuel phragm-.air pressure being admitted to the delivery passage 16 may, be controlled by -a outer surface of the non-resilient diaphragm referred to, even thou hl said surface be roreciprocating diaphragm 13 comprises a tected by a downwar ly concave guar respring 1 8 conditionally operative to effect an sembling that disclosed in the Zubaty et al. intermittent expulsion'of fuel froml the chamapplication, but perforated or formainous. ber 12 past valve 17, such expulsion being deL Broadly, it is an objectof this invention to pendent upon a pressure differential between replacement of .a valve plug, permitting Any desired means such as a lost motion some utilization of any momentum, such as linkage 19,- effective under tension but inlimparted to a liquid fuel by a reciprocatory to impart an intake movement to the diafuel pump, `in promoting a continuousl adphragm 13, or its equivalent; but'it will be vance ofpumped fuel through some part of understood that, although links 19 and l20 are a fuel line;and it is'an es pecial merit of the respectively pivoted at 22 to a slidable ele-4 construction herein descri edv that the use of ment 23 (carrying a nut 24 for the retention the mentioned vfabric diaphragm, or its of plates 25 and 25', by which the diaphragm equivalent, renders the pulsator unit ,contain- 13 is shown4 as secured) and, at 26, to a lever ing the same highl sensitive to pressure difv2"?, movable upon apivot 28 by means such as ferentials. For t e foregoing reasons, the any reciprocating -or rotatingengine-driven pulsator herein described andclaimed is repart, Athese details are of minor importance erred to as an inertia-effect pulsator.

A`herein. l .Other objects of this invention, which may The closure plate or casting 11, shown as -be broadly described as comprising a hollow carrying an inserted valve seat 29 for the body to whose interior 4liquid fuel is afioutlet valve 17, may carry also q sl'ght-cup similar valve 17. The illustrated means for v 4not shown, may be-admitted by way of the cup 30 and past the intake valve ,15.

Coming now to preferred details of the novel pulsatorto whose protection the present application is directed, a hollow body 31,

preferably adapted to receive a wrench or the like, is shown as externally-threaded at 32 and is provided with an inclined or other duct 33, serving to establish constant communication between a passage 34 in said body and the kvoutlet passage 16. The hollow body 31 is preferably vprovided not only with a downward extension 35, serving to retain and guide a spring 36 (tending to seat the valve 17)v but also with means for supporting'a non-resiliert diaphragm 37.

For they purpose last referred to, and to provide avariable-volume auxiliary container 38, beneath the diaphragm 37 and in communication withthe passage 34,an upwardly concave part 39 is shown peripherally secured to said diaphragm and mounted uponan upwardly extending reduced portion 40* of 'the body 31, the reduced portion being shown as swaged or headed down over the concave part 39, although a soldering or other equivalent operation might be here employed. An optional element may have the form of a downwardly concave part 41; and this part 41, .shown as perforated at 42, may be adapted not only to serve as a guard element protecting the diaphragm 37 assuming the latter to be formed of cloth, suitably treated to render the same impervious to liquid fuels, but also peripherally to secure the upwardly concave part 39 (whether the latter isresilient or rigid) to the said diaphragm, or to any equivalent iexible but substantially inextensible diaphragm element. not resilient and not secured under such tension as to prevent it'from responding t'o pressure differentials.

The coating and/or composition of the diaphragm 37, although there need be no novelty in the material or materials'used, may be such asl to ob'viate the requirement of any gasket in connection with a joint serving to secure the parts 37 and 39 together, as by the crimping or pressing of a peripheral edge of the guard element41 thereover in the general manner suggested at 43; and it willbe obvious that the construction herereferred to is both simple and inexpensive aswell as durable and reliable.

As to mode and theory. of operation, the use of a slack-cloth diaphragm ofthe described character, eliminating all necessityl for a resilient metallicv diaphragm or for an a1r veslcle or any other resilient vmembers as heretofore used, renders possible the 'utili-- zation of the inertia of the liquidcontained 1n the delivery line (as, between the described described character during each expulsion` stroke of the diaphragm 13, or an equivalent reciprocatory pumping element; and, notwithstanding such a prompt closure of the valve 17 as would otherwise interrupt the consequent How of fuel through the outlet 16, the exibility of the diaphragm 37, rendering the same especially sensitive to such pressure differentials as may .occur when the need of fuel is greatest, may adapt the same promptl to descend upon the closing of the valve 17 in such a manner as to permita substantially uniform flow, or at least an uninterrupted uni-directional flow, of fuel toward a carburetor of any suitable type (not shown).

It will be obvious that the described mode of operation involves a decreased peak pressure upon the pump diaphragm 13, thus allowing its spring 18 to move upward farther in ay given length of time and to force a ,greater volume of liquid out' past the valve y17,; but' nol effort is at present made separately to evaluate the factors upon which the eficiency of the pulsator unit of the described general character may depend.

Although but a single type of pulsator illust'rative of the principles of this invention is above described, it will be obvious that numerous additional forms might easily be the notable results obtained appear to be due mainly to .inertia effects.

I claim:

1. For use in continuous communication with a line into which liquid fuel is intermittently delivered, an inertia-effect pulsator unit comprising: a hollow main 'body pro- 'y vided with a communicating passage; a part serving to support a diaphragm element from said body? and a `non-resilient but flexible diaphragm carried by said supporting part and outwardly exposed to atmospheric pressure.

' 2. A pulshtor as defined in vclaim 1 in which said main body is threaded suitably for use as a valve plug.

e. A pulsator as defined in daim 1 in which said diaphragm is a slack-cloth diaphragm.

4. A pulsator as defined in claim 1, in which said diaphragm is a slack-cloth diaphragm secured by adownwardly concave part which serves as a guard element there- 5. Apu1sator as defined in claim 1 in which said diaphragm' is provided with 'a guar'd element' havlng a constantly open aperture to admit air pressure thereto.

6. For use in an automobile fuel pump line, a ow-equalizing inertia-effect means comprising: a nonresilient diaphragm; and means for so securing said diaphragm as to admit the fluctuating pressure of a pumped fuel to one'side thereof while freely passing external air pressure to and from the other side thereof. In testimony whereof I aix my'si ature.

. LUCIAN B. SLTH.

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